Temperature control



Jan. 22', 1935.,

G. E. HULSE ET AL TEMPERATURE CONTROL Original Filed Feb. 12, 1931 2 Sheets-Sheet 1 1 J A gvfimom cE LA AITORNEYS 2 Sheets-Sheet 2 TEMPERATURE CONTROL Original Filed Feb. 12, 1951 G. E. HULSE ET AL /02 V /9 //f {a k a oooLMMoooo a as . Jan. 22, 1935.

INVENTORS LWwM ATTORNEYS Patented Jan. 22,1935

PATENT OFFICE TEMPERATURE comor.

George E. Boise and John D. Strobell, New Haven, C onn., assignors to The Safety Car Heating 8: Lighting- Company, a corporation of New Jersey Application February 12,1931, Serial No. 515,200 t Renewed July 25, 1934 36 Claims.

This invention relates to a method and apparatus for controlling the temperature'of the atmosphere in a space, such as a room, railway car, or the like.

One of the objects of this invention is to provide an atmosphere-conditioning apparatus of simple and practical construction and reliable operation. Another object of this invention is to provide an apparatus and system of the abovementioned character which will be of ready and economical construction and which may beinstalled with ease. Another object of this invention is to provide a system and apparatus of the above-mentioned character which will be thoroughly capable of long continued action.

Another object of this invention is to provide an apparatus and system of the above-mentioned character which will be highly efficient and well adapted to meet many peculiar conditions commonly met with in practice. Another object of this invention is to provide a system and apparatus of the above-mentioned character which will dependably maintain the temperature in a space at a comfortable value at all times in spite.

of various weather or climatic changes. Another object of this invention is to provide a system and apparatus of the above nature which will be automatic in operation and ,maybe operated by-unskilled labor with little, if any, risk of disarrangement'of any of its parts. Other objects will be in part obvious and in part, pointed out hereinafter. 1

This invention accordingly consists in the features of construction, combinations of elements, arrangements of parts, and in the several steps and relation and order of each of the same to one or more of the others, 'all as will be illustratively described herein, and the scope of the application of which'will be indicated in the following claims.

In the accompanying drawings in which of our invention, there is diagrammatically indi-' cated in Figure 2a space 10 which may take any suitable form, such as a room, railway-car or the like, whose temperature is to be regulated. Disposed within the space is a conduit generally indicated at 11 having suitable outlets 12 so positioned as to conveniently discharge air therefrom to all portions of space 10. The

mouth 13 of conduit 11 is so positioned that-it receives fresh air from the exterior of space 10, and mounted in any suitable manner adjacent mouth 13 is a motor 14 for driving a fan '15. Thus the energizat'ron of this motor and consequently the actuation of fan 15 forces a draft" of fresh air through conduit 11 and out through outlets 12, to be circulated throughout all por.

were installed on a railroad car, in order to provide a suitable source of current to actuate motor 14 and various other electrical parts of our system to be described hereinafter, we provide a generator 16 driven from the car axle'and a storage battery 17. Disposed between generator 16 and storage battery 17 is an automatic switch 18, of any suitable construction, connecting the generator to the battery when its voltage is adequate and effecting disconnection when generator voltage drops below a certain value. In the latter case the battery 17 acts as the source of current for our system and in the former case the generator acts as this source.

.Insofar as the broader aspects of our invention are concerned, any other suitable means for generating a dependable and suitable supply of current for this system might, be. substituted for that described herein.

Lines 19 and 20 leading from battery 17 are "connected to one side of a manually operated switch 21 and the other side of this switch is connected to motor 14 by lines 22 and 23. i In this manner, when switchj21 is closed, a circuit is established between battery 17 or generator 16 and motor 14 consisting of line 19, switch 21,

line 22, motor'14, line 23, switch 21 and then by tages, we provide two adsorbers 24 and 25 (Fig.

2) so that one may adsorb gaseous refrigerant while the other isreleasing the refrigerant in a manner to' be described hereinafter. Disposed within these adsorbersis a substance adapted to take up gaseous refrigerant when cooled and to :release' gaseous refrigerant when heated. This substance may take the form of silica-gel which may be contained therein by any suitable means for allowing a fluid to pass into thermal contact therewith to impart heat thereto or to abstract heat therefrom in a manner to be described hereinafter. A pipe 26 is connected to one side of adsorber 24 and is in turn connected to a condenser 27; the corresponding side of adsorber- 25 is connected to pipe 26 by a pipe 28. A check valve 29 is positioned in pipe 26 adjacent adsorber 24 and is so constructed that it opens by pressure-exerted upon it on the adsorber side thereof; hence it is opened when adsorber 24 is heated to release gas and remains closed when adsorber '24 is being cooled to take up gas. A check valve 30 similar. in construction to check valve 29 is positioned in pipe 28 and remains open under the gas pressure exerted when adsorber 25 is'releasing gas upon the application of heat thereto, closing when adsorber 25 is cooled to take up gas. Coacting with valve 29 is a check valve 40 disposed at the opposite end of adsorber 24 and so constructed that, when valve 29 is open'to release gas from the adsorber,

valve 40 is closed by the pressure of gas being released, and, conversely, when valve 29 is closed, as is the case when adsorber 24 is takingup gas, valve 40 is opened by the greater pressure exerted by the gas in pipe 37. Coacting with valve 30 is a valve 39 similar in construction and ac tion to valve 46 as described above.

4 Assuming that the gas is being driven off by heating adsorber 24 and that adsorber 25 is be-- ing cooled to take up gas, the gaseous refrigerant emanating from adsorber 24 passes down the pipe 26 (valve 29 opening automatically and valve 30 being closed) to be condensed in condenser 27. Condenser 27 may beof any suitable construction to cool the gas and thereby liquefy it. The liquefied gas is conducted from condenser 27 to a float valve generally indicated at 31 by a pipe 32. This valve comprises a chamber 33 through the bottom of which extends a pipe '34, the upper end of which is controlled by a valve member 35 seated therein and actuated by a float 36. Thus the liquefied gaseous refrigerant is maintained in chamber 33 at a level with the top of pipe 34 and when liquefied refrigerantenters the chamber, float 36 rises to' unseat valve 35 and allow the refrigerant to pass down pipe 34. The liquid refrigerant entering pipe 34 is conducted to an expansion coil 36 disposed in mouth 13 of conduit 11 adjacent fan 15, where evaporationtakes place. The evaporation of the liquefied refrigerant requires heat and as this coil is located inmouth=13,- the air being forced by the fan- 15 past the coil is cooled. As adsorber 25 is being cooled to-takeup gaseous refrigerant, the gas pressure is greater in pipe 37 than inside. of adsorber'125 and the expanded gas passes through a pipe 37, pipe 38,

and through-check valve-39 to adsorber '25,

Check valve 40 is closed, for adsorber 24 is being heated to release gas and the pressure of the latter keeps valve 40 closed. Thus the gas released by adsorber 24 is ultimately adsorbed by adsorber 25, and when this has substantially taken place, adsorber 25 is to be heated and adsorber 24 cooled.

If, now, adsorber 25 is being heated and adsorber 24 is being cooled, the pressure in the latter is insufficient to open valve 29 which remains closed, but valve 30 is opened by the pressure within adsorber 25 to allow gaseous refrigerant to pass from adsorber 25 through pipe 25 to the condenser 27 and other parts of the refrigeration unit and ultimately -to evaporator coil 36 and thus refrigeration takesplace in coil 36 as described above. The expanded or evaporated gas from coil 36 passes through pipe 37 (valve 40) and enters the cooled adsorber 24, wherein the pressure is now lower than in pipe 37 and hence valve 40 being open; but in adsorber 25 the pressure is greater than in pipe 37 and hence valve 39 remains closed. In this manner the cooling action in coil 36 is continuous as long as one of themdsorbers is being heated while the other is being cooled, and it will be seen that by alternately heating and cooling these two adsorbers, the silica gel or other agent contained in one adsorber may be replenished with gaseous refrigerant resulting from evaporation in the evaporator while the other is releasing gaseous refrigerant for refrigeration purposes. Themanner by which we provide for alternately heating and cooling these adsorbers and for controlling this action will be described hereinafter.

Heat may be extracted from the refrigerant in" condenser 27 by any suitable means, and illustrlatively we have shown condenser 27 as water cooled by means employing the same water over and over. This is especially advantageous if our system is installed on a railroad car or some other form of passenger vehicle where the supply of water is limited. In order to keep the cooling water supplied to the condenser at a suitable low temperature, we provide a cooling tower which includes a tank 41 into which the warmed water from the cooling coil 27 of condenser 27 is led by a pipe 42 discharging through a suitable spraying device into the upper portion of this tank. A fan 43 driven by a motor 44 is disposed at one side of the tank to blow. suflicient cooling air in counter-current relation to the water spray emanating from pipe 42 at the top of tank 41 while suitable vents 41' are provided in the top of tank 41 'so that this current of air may passto the exterior thereof.

A pipe 45 leads from the bottom of tank- 41 to the inlet of a rotary pump 46 whose discharge is ,connected to cooling coil 27 of condenserv27-by a pipe 47. Pump 46 is driven by a motor 48 through a shaft 49.

Thus the actuation of motor 48 drives pump 46 to initiate a withdrawal of cooled water from the bottom of tank 41 through pump 46-by pipe 45 and thence to condenser 27 bypipe 47. The warmed water completes the pathof circulation by entering tank 41 through pipe .42 where it is sprayed down past the air current from fan 43 and is again. cooled. Motors 44 and 48 are arranged for simultaneous control and actuation. The circuit of motor 44 leads from one side of switch 21; conductor 50, motor 44, conductor 55, movable contact 54 .of aswitch generally indicated at 53 (Figure 1), contact 52 and conductor In this manner when adsorbers 24 and 25 are actuated to produce refrigeration in expansion coil 36, in a manner to be described hereinafter, fresh air forced past coil.36 byfan 15, when out hereinafter, however, it is desired to heat this air passing through conduit 11, and to accomplish this we provide a heating member, preferably in the form of a pipe coil 58 suitably disposed in mouth 13 of cond t 11 and adjacent fan 15. Connected to a suita le sourceof steam, such as the train steam line, is a pipe S (Figure 1) from which steam is led to coil 58 by pipes 60 and 59, through a valve 61, from which a pipe 62 leads to 001158 (Figure 2) If valve 61 is open, steam passes therethrough and into pipe 62 to be conducted thereby to coil 58. The steam thus passing through coil 58 heats the air passed through conduit 11 when motor 14 is running. The exhaust steam leaves coil 58 by a pipe 63. In this manner, coil 58 acts as a heating member for space 10, and this action is dependent upon the control of valve 61 and the actuation of motor 14.

As will now be clear from the foregoing, it

. for bringing steam, preferably from the abovementioned source, into thermal contact there- ,with. Pipe. 60 (Figure 1) leads from pipe S,

which is connected to a suitable source of steam, as described above, to a pipe 65 (Figure 2), con nected to avalve 64,. the other side of which is connected to a pipe '66. Pipe 66 is in turn connected to adsorber 24 by a pipe 67. Thus steam in pipe 60 may be conducted .to adsorber 24, when valve 64 is open, through pipe 65, valve 64, pipe 66 and pipe 67. The exhaust steam leaves adsorber 24 through a pipe 68 which leads to a pipe 69, and pipe 69 is connected to one side of a valve 70. The other side of valve 70 is connected to a pipe 71' leading to a pipe 72 through which the exhaust steam may be suitably disposed of. When valve 64 and valve 70 are both open, a' continuous flow of steam passes through adsorber 24 through the path as described above, and in this manner this adsorber may be heated to cause it to give up the gaseous refrigerant to condenser 27, through pipe 26.

To heat. adsorber by steam, the steam in pipe 60 is conducted by a pipe 73 to one side of a valve 74. When valve 74 is open, the steam passes into-a pipe 75 and then by way 'of pipe 76 is conducted into adsorber 25. The exhaust steam from adsorber 25 is conducted through a pipe 77 and a pipe 78 to one side of a valve 79, and, if valve 79 is open, the steam passes into pipe 72 by way of pipe 80. Thus the heating of adsorber 25 by steam is dependent upon. the opening of valves 74 andr79, and thus adsorber 25 may be made to deliver gaseous refrigerant to condenser 27.

Considering now the means employed for cooling adsorbers 24 and 25, we prefer to bring cooling water into heat-abstracting relation to these open, the water passes by way of pipes 66 and 67 to the adsorber 24, valve 64 being closed, as will be described hereinafter. The water is thus conducted into cooling relation with adsorber 24,

to cause the adsorbent therein to take up gaseous refrigerant from evaporator 36; and the warmed water leaves the adsorber through pipe 68 to enter pipe 69. Pipe 69 is connected to a valve 87, and, if this valve is open and valve 70 is closed, the water passes through valve 87 into a pipe 88 and thence into a discharge pipe 89. Pipe 89 is connected to dispose of the water in any suitable manner. Thus if valves 86 and 87 are open and valves 64 and 70 are closed, cooling,

water passes through adsorber 24, this action, of course, being dependent upon the opening of valve 82.

Water for cooling adsorber 25 passes from pipe 83 (Figure 2) through a valve 90 when this valve is open, whence it is then conducted to the adsorber by pipes 75 and 76, with valve 74 closed, and leaves the adsorber by pipes 77.and 78 under the control of a valve 91 connected to discharge pipe 89. The closing of valve 79 and openingof valve 91 allows the warmed water from adsorber 25 to pass into the discharge pipe 89. Thus adsorber 25 may be cooled by water if valves 82, 90 and 91 are open and valves 74 and 79 are closed.

By this arrangement of parts we have provided means for alternating heating and cooling adsorbers 24 and 25. Thus if valve 82 is open to allow water to pass into the system and steam is being supplied through pipe 60 (Figure 1),

one of the adsorbers may be heated while the other is being cooled to cause refrigeration to take place in a manner described hereinabove. Under these conditions if valves 64, 90, 91 and 70 are open, and valves 87, 79, '74 and 86-are':

89. While water is flowing through adsorber 25 so that the substance contained therein is taking up expanded gas from expansion coil 36 in'the manner described above, steam from pipe passes into pipe through valve 64, pipe 66, pipe 67 to adsorber 24 and the exhaust steam is disposed of through pipe68, pipe 69, valve '70, pipe 71 and pipe 72. Thus adsorber 24 is being heated to release gas, and this gas is conducted through valve 29 and pipe 26 to start the cycle:

of refrigeration.

After a period of time, the gas supply in adsorber 24 may be exhausted and adsorber 25 may have reached the saturation point for ad-' s'orbing gas so that the reverse action becomes necessary for achieving continuous refrigera tion; more 5 ec'fieally, there should now take place a heating of adsorber 25 and a cooling of adsorber 24. This may be accomplished if valves 86, 74, 79 and 87 are open and valves 64, 90, 91 and are closed- With this relation of parts, steam passes through adsorber 25 by pipe 60, pipe 73, valve 74, pipe and pipe 76 and 'is then disposed of through pipes 77 and 78, valve 79, pipe and pipe 72. Simultaneously with this action water from pipe 81 passes through valve 82, pipe 83, pipe 84, valve 86, pipe 66 and pipe 67 to adsorber 24. The warmed water leaves adsorber 24 through pipe 68, pipe 69, valve 87, pipe 88 'and pipe 89'. Thus the reverse action takes place and adsorber 24 is cooled take up gas. from' expansion coil 36 while a sorber 25 is being heated to give off gas to condenser 27 through valve 30, pipe 28 and pipe 26.

In this manner adsorbers 24 and 25 may be alternately heated and cooled by the proper operation of valves 64; B6, 74, 90, 91, 79, 87 and '70, and these valves are automatically controlled, as will 'be presently described in detail. Conveniently and preferably these valves are fluidoperated, being suitably constructed to be opened by the application of fluid under pressure and to be closed upon the release, from the operating parts thereof, of the pressure of the controlling or operating fluid. Also, the latter is preferably compressed air.

To actuate these various valves as well as various other parts of our system, we, therefore, provide a suitable source of compressed air. As our system and apparatus have many advantages and conveniences admirably adapted to meet the unusual and varying conditions met with in passenger vehicles, such as railroad cars, and as there is usually an abundant supplyof compressed air associated with these vehicles for the braking system and other purposes, we have provided a tank 93 (Figure 1) which receives compressed air from the auxiliary reservoir 94 in the air-brake system of such a car, but in a manner-to prevent such bleeding of the air-brake system as would make the latter inoperative. A one-way check valve 95 is interposed between auxiliary reservoir 94 and tank 93 and is so adjusted that it does not allow air to pass from tank 94 to tank 93 unless the pressure in tank 93 has fallen below a certain value. 7 v

For purposes of illustration, let it beaassumed that tank 94 contains air at a pressure of approximately 125 pounds per square inch. Valve 95 is so weighted with a spring (not illustrated) that an effective pressure of pounds per square inch thereon is required to open it and pass air therethrough. If the pressure in tank 93 falls below 25 pounds per square inch, the effective pressure on valve 95 is greater than 100 pounds, and this valve opens to pass air into tank 93. Thus valve 95 remains closed against the 125 pound pressure in tank 94 because of the 25 pound pressure in tank 93 plus the 100 pound pressure of the spring in the valve. In this manner interference with the operation of the air-brake system is prevented since it is impossible to drain that system below 100 pounds pressure, a pressure that, by way of example,

may be assumed to be the minimum operating.

pressure for the air-brake system.

From tank 93 (Figure 1), air is led to an air motor 102 (Figure 2) byway of pipes 97 (Figure 1), 98', an electrically controlled valve 99, pipe 100, pipe 101 (Figures 1 and 2)., and a camcontrolled' valve 105. Air motor 102 is preferably of the diaphragm type and is so constructed that, for a substantially constant pressure of air supplied to it, it drives a cam 103 connected thereto at a definite speed. Thus if the pressure of. the air supplied to motor 102 is 25 pounds per square inch, it maybe assumed that motor 102 rotates cam-103 one complete revolution for every two;hoursduring which air issupplied'to the motor. As will be pointed out hereinafter, motor 102 is so controlled t when once started, it continues in action un cam 103 has made one complete rotation: Air- 'is supplied to motor 102 from tank 93 (Figure 1) through pipe 97, pipe.98, valve 99, pipe 100 ,and pipe 101 (Figures 1 and 2), and, as will be presently seen, this circuit of supply of air is for starting the motor; thereafter the air supply shown) driven by motor 102. Ifvalve 105 is open, air under pressure is supplied to the motor from tank 93 by pipes 96 and 104. Valve 105 and its controlling cam are so constructed that the valve is held open for almost a complete revolution of cam 103, but just before the completion of the revolution, valve 105, under control of this cam, closes, to shut 011 the supply of air to motor 102. Motor 102 stops, and does not again start until valve 99 (Figure 1) is opened. However, if valve 99 (Figure 1) is open, when the one revolution is completed, the motor 102 continues tooperate, receiving air under pressure, this time through pipe 101,. whereupon valve 105 is again opened and held open during one complete revolution; but if valve 99 remains closed, valve 105 having closed at the end of one revolution of cam 103, no air is supplied to the motor and it remains at rest.

Cam 103 is so constructed that preferably one half portion 106 thereof is of greater diameter than the other half portion 107. Two oppositely disposed valves 108.cand 109 are positioned adjacent cam 103 and'air from pipe 96 is supplied toone side thereof by branch pipes 110 and 111 respectively. An arm 112 extends from valve 108 and is in substantial engagement with the cam periphery of cam 103. The valve is so constructed that when arm 112 is moved to the right against'the tension of a spring (not illustrated) and into the position shown in Figure 2, valve 108 is open, thus to supply air to a pipe .114, and a subsequent movement to the left of arm 112 closes the valve, thus to shut 011 air from pipe 114. Valve 109 is similar in construc-x tion and action to valve 108 andhas an rm 113 engaging the cam periphery of cam 3 to operate the valve and thus to control the sup ply of air to pipe 115.

Thus when portion 106 of cam 103 is in engagement with-arm 112 of valve;108, arm 112 is moved to the right and valve 108 is opened (as shown in Figure 2). The opening of valve 108 allows air under pressure to pass from pipe 110 through the valve and thence into pipe 114. Simultaneously with this action, cam portion 107 of cam 103 is in engagement with am 113 of valve 109 (as shown in-Figure 2) and in this position valve 109 is closed, thus to shut off air from pipe 115. As the cam rotates and portion 106 comes into engagement with arm 113, however, valve 109. is opened to admit air under pressure to pipe from pipe 111 while cam portion 107 causes valve-"-108 to close. In this manner during one-half of a revolution of cam 103, valve 108 is open to supply pipe 114 with air under pressure, and valve 109 is closed, and during the other half of the revolution, valve 109 is open to supply air under pressure to pipe 115 and valve 108 is closed. r

' A pipe 116 connects pipe 114 with valve 90, ,which, as described above, is pneumatically actuated as are valves 64, as, 14,91, 79, 87 and 70. and a pipe 117 connects pipe 114 to valve 64, while a pipe 118connects valve 91 to pipe 114 and a pipe 119 connects valve/70- to pipe 114. Pipe'115 is connected to valves 86 and 74 by pipes 120 and 121 respectively, and valves 87 and 79 are connected to pipe 115 by pipesv 122 and 12a. Valves '10, a7, '19, 91, 9o, 74, as and 64' transmitted by pipes 117, 116, 118 and 119 to valves 64, 90, 91 and 70, respectively, to open them. As valve 109 is closed, no fluid is admitted at this time to valves 87, 79, 74 and 86, and these valves remain closed. With the parts in this condition; steam is admitted to adsorber 24 to impart heat thereto and water is admitted to 'adsorber 25 to abstract heat therefrom in,a'

manner described above. When portion 106 of cam 103 engages arm 113 of valve 109, this valve opens and valve 108 closes. Thus air under pressure is admitted to pipe and transmitted therefrom by pipes 122,123, 121 and to valves 87, 79, 74 and 86 respectively, and these valves open. Simultaneously air pressure is removed from valves 64, 90, 91, and 70 to close these valves. With the parts in this condition steam is admitted to adsorber. 25 and water passes through adsorber 24. If, as above "assumed, motor 102 drives cam 103 at the speed of one revolution in two hours, it will be clear from the foregoing that one) adsorber is steam-heated for a period of one hour while the other adsorber is being water-cooled, and the opposite action takes place during the following hour.

Thus under these conditions, as long as motor 102 is supplied with air under pressure, these alternate cycles of heating and cooling continue to take place, and this action. in turn is dependent upon the action of cam actuated valve 105 and electrically actuated valve 99. More speciflcally if valve 99 closes, air is still furnished the, motor through valve 105 until the completion of the cycle of alternate heating and cooling asdescribed above. Furthermore, valve 99 (Figure 1) is connected by pipe 100 to a bellows 124 for actuating switch 53 by means of an arm 125.v When. valve 99 is opened and air under pressure is conducted through pipe 100 to bellows 124, contact 52 of switch 53 engages contact 54. As described above, when manually operated switch 21 is closed, switch 53 controls the circuit between generator 16 and/or battery 17 and motors 46. and 48. Thus the closing of switch 53 actuates these motors to initiate the cooling action for the condenser cooling water as described above. Thus the electrically actuated valve 99 controls the refrigerating action of our system, for when this valve is opened, air is supplied for starting motor 102 through pipes 100 and 101, and bellows 124 is also actuated to close switch 53 and make effective the condenser 27 to receive and condense gaseous refrigerant emanating from-that adsorber whose I heating has beenst'arted by motor. 102.-

Pipe 97 (Figure 1) leading fromthe source of air under pressure is connected to a 'pipe' 126 which is in turn connected ,to one side of an electrically actuated valve 127., The opposite side of valve 127 is connected by a pipe 128 to fluid-actuated valve 61. When valve 127 is open compressed air is therebyfurnished from tank 93 to the actuating parts of valve 61, and as this valve is so constructed as to open upon the application of fluid under, pressure to its operating parts, this valve opens upon the opening" of valve 127, but closes when closure of valve 127 cuts off the fluid or air therefrom. The opening 'of valve 61 allows steam from the sources to pass therethrough into pipe 62 and from.

thence to the steam heating coil 58 (Figure 2) as described above.' Valves 99 and 1 27 are of any suitable electro-magnetic construction so that energization thereof from a suitable source of current opens them and de-energization closes them.

Thus if valve 99 is energized to open, refrigeration is'furnished to space 10 through conduit 11, and if valve 127 is energized to open, heat is furnished to space 10 through conduit 11.

A bulb 129 (Figure 2) disposed within space- 10 in any suitable manner so that thermal changes within the space will correspondingly affect the temperature of a substance contained therein. A suitable volatile liquid is contained f tacts 136 and 137 coacting with contacts 138 and 139 according to the angular position of arm 134.

Contact 139 is manually adjustable so that its position with respect to a suitably graduated temperature scale 140 may be determined and fixed before or during the operation of our system. Thus a transverse motion of rod133 ini-- tiated by bellows 132 in response to an increase or decrease in the vapor pressure of the volatile liquid contained therein and in bulb 129 (Figure 2) moves arm 134 to engage contacts 136 and 138 or contacts 137 and 139. Contact 138 is secured to one end of a member 141 which is slidably guided by studs 142 and 143 for movement toward the right as viewed in Figure l, and which in its normal position is held against studs .142 and 143 by the pressure of a spring 144, studs 142 and 143 thus acting as stops. Spring 144 is seated at 145 so that the pressure applied by spring 144 to member 141 acts against stops 142 and 143. Contact 138 is of such a length with respect to the position of stops 142 and 143 that contactl36 is out of engagement therewith larposition of arm .134. Contact 139 is adjusted accordance with this scale so that contact 137 9 does notcome into engagement therewith for any reasonable temperature below 70"..

A- thermostatic'bulb 146 (Figurel), similar in construction to the above-described thermostatic bulb 129, is disposed outdoors or outside- 0f space 10, whose. temperature is to be regulated, and

' perature within space 10 according to the anguconnected thereto bya pipe 147 is a bellows 148 like bellows 131 and actuated by changes in pressure therein due to temperature changes aflecting the vapor pressure of a suitable volatile liquid contained in bulb 146. An arm 149 pivoted at 150 is in turn pivotally connected to a rod 151 connected to the free or unanchored end of bellows 148. The upper end of arm 149 has secured thereto a contact 152 insulated therefrom and adapted to coact with two relatively fixed contacts 153-and 154. Contacts 153 and 154 are so constructed that they may be normally adjusted and fixed with respect-t0 a suitably graduated temperature scale. 155. Scale 155 is so graduated as to indicate by the angular position of arm 149 the temperature (outside of space 10) affecting the vvolatile liquid contained in bulb 146. Thus for purposes of illustration contact 153 may be adjusted so that contact 152 does not engage therewith until a temperature at or below 68 outside the space 10v has been reached, and contact 154 may be so adjusted that contact 152 does not engage therewith unless affected by a temperatureoutside of space 10 at or above Secured to and movable with arm 149'and related so that its end 156 can engage movable member 141 is an extendable member generally pass therethrough to indicated at 157. Member 157 is preferably adjusta-ble in length and consists of two overlapping parts 158 and 159, one of them, part 158. being slotted to receive clamping screws 160 and 161. In this manner, member 157 may be adjusted to any desired length, and the point at which it engages to exert pressure, against and move member 141 in a right hand direction may thus be predetermined. Hence the distance between contacts 138 and 139 may be varied in accordance with the angular position of am 149 and the length of arm 157. Likewise, the point at which contact 136 engages contact 138 is determined bvthese two factors.

The coaction of the various contacts above describedcontrols. circuits between a battery 162 or any other suitable source of current and electro-magnetic valves 99 and 127. With the parts in the positions shown in Figure 1, a circuit is established between electro-magnetic valve 99 and battery 162, this circuit extending from battery 162, line 163, contact 152, contact 154, line 164, contact 136, contact 138', .line 165, valve 99, and then line 166 back to battery 162. Upon the completion of this circuit, valve 99 is energized to open so that air under pressure may initiate refrigeration in a manner described above.

If arms 149 and 134 are swung in a counterclockwise direction by bellows 148 and 131 re-'- spectively so that contact 152 engages contact 153 and contact 137 engages contact 139/a circult is established between battery 162 and electro-magnetic valve 127., The circuit so established extends from battery 162, line 163, contact 152, contact 153, line 167, contact 137, contact 139, line 168, valve 127, line 169. and then line 166 back to thebattery 162. The completion of this circuit energizes valve. 127 to open this valve and let air under pressurev through pipe 128 to openvalve 61 and thereby initiate the heating action in steam coil 58 (Figure 2). Among certain disadvantages and dimculties met with in the cooling of, for example, the interlor of; a room is the 'discomforting'and undesired difference in temperature when the temperature of the room is maintained at a relatively fixed value and when the temperature of the exterior thereof varies between wide limits. Our system is well adapted to avoid such disadvantages and, for purposes of illustration, let it be assumed that it is desired to maintain a difference of 5 F. between the outside temperature and the temperature within space 10. Also, let it be assumed that the outside temperature is 75 F.; hence the temperature desired to be maintained within space 10 is 70. Let it also be assumed that the temperature within space 10 is now 73 and is at no time to be reduced below 68.

We first set contact 153 at the 68 position so that movable contact 152 engages or disengages contact 153 when the outside thermostatic bulb 146 is affected by a temperature of 68. In a similar manner we set contact 139 at the 68 position. so that contact 137 engages or disen-' gages contact 139 when theinside thermostatic bulb 129 is affected by a temperature within the space 10 of 68 or less. Contact 154 is set at the 73 position or thereabouts (a few degrees higher than the setting of contact 153) so that contact 152 engages or disengages contact 154 when outside thermostatic bulb 146 is affected by an,

21 (Figure 2) to supply currentfor the system and thus immediately actuate motor 14 (Figure 2) driving fan 15. Fan 15 is now forcing air past coils 58 and 36 into conduit 11 and thence into space 10 through outlets 12 and the temperature of the space, which we have assumed to be the interior of a railroad car, may now be regulated in accordance with the effectiveness of steam coil 58 or expansion coil 36.,

Arms 149 and 134 under the above assumed conditions now occupy positions substantially as shown in the drawings. As refrigeration is required in space 10 under the above-assumed temperature values, it will be noted that the parts are now in condition for such refrigeration which is to be continued until the temperature is brought down to 70 F. or 5 lower than the outside temperature. A circuit is now established between elecro-magnetic valve 99 and battery 162 as described above and this valve opens to condenser 27 and the condenser is now placed in effective condition for operation. Simultaneously with this action, air under pressure passing through pipe (Figure 1) enters pipe 101 to start air motor 102 (Figure 2). Thus motor 102 is actuated and cam 103 starts revolving and the initiation of this action opens cam actuated valve and holds it open for one complete revolution of cam 103, in a manner described above. Alternate cycles of heating and cooling take place in adsorbers 24 and 25 and there- I both contacts, however, remaining in engagefrigeration cycle is established so that cooling action takes place in expansion coil 36. The air passed thereby by fan 15 and thence into space 10 through outlets 12is now cooled and cools circuit between valve 99 and battery 162 is broken and this valve closes. Bellows 124 contracts to disengage contacts 52 and 54, thus stopping motors 46 and 48. At the same time the supply of air to motor 102 through pipe 101 is cut off. However, motor 102 is supplied with air through pipes 96 and 104 until the completion of the revolution of cam 103. At the end of this revolution, however, valve 105 closes to stop the motor and thus the alternate heating and cooling of adsorbers 24 and 25 ceases. As this action ceases, the refrigeration stract heat from the air passing thereby into conduit 11. However, should the temperature of space 10 rise above 70, the vapor of the volatile liquid contained in bulb 129 exerts a pressure on the unanchored end of bellows 131 to move contact 136 into engagement with contact 138. Thus refrigerating action again takes place until the temperature of space 10 is again brought down to 70.

Let it be assumed, however, that the outside temperature rises to 78 and, as described above,

a fixed difference between the outside and inside temperature of is to be maintained. To establish this difference now, the inside temperature must be maintained at 73. Thermostatic bellows 148 is now'aifected by this increase in temperature through the action of the contents of bulb 146, and thus movesarm 149 and consequently contact 152 farther along contact 154,

merit with each other.- As this action takes place the extendable member 157 is also moved to the right and, being already in engagement with movable .member 141, thus moves this member and contact 138 to the right throughout a distance corresponding to the increment of increase in outside temperature. Thus the parts are now positioned so that contact 136 on arm 134' does not engage contact 138 until a temperature of 73 inside space has been reached. Further, no refrigeration in coil 36 and consequently no cooling takes place until a temperature of 73 is exceeded in space 10. When such a temperature is reached, contact 136 engages contact 138, thus completing the circuit between battery 162 andvalve 99, and the refrigerating parts, as described above, are actuated to cool space 10 until the temperature therein is re-- stored to 73.

For purposes of illustration, let it be assumed that it is a very hot day and the outside temperature is 90 F. In such a case it may be desirable to. have a greater difference between the temperature inside the space and the temperature outside the space in order to maintain a comfortable temperature therein. To provide for this greater difference in temperature, screws 160 and 161 are loosened and member 157 is shortened'so that the end 156 thereof does not position with respect to temperature scale 155, thus being moved toward the right of the position in which it is shown in the drawings (Figure 1). Simultaneouslywith this action member 157 exerts a pressure against movable member 141 5 and against the action of spring 144 to force this member to the right. The length of member 157 has been so adjusted that when arm 149 assumes its 90 position, contact 136 on arm 134 does not engage contact 138 until a temperature of 80 is 10 reached within space 10. As contact 152 is in engagement with contact 154, the completion of the circuit between battery 162 and valve 99 is dependent upon the engagement of contacts 136 r and 138. Thus refrigeration does not take place in space 10 until the temperature of that space reaches 80 or above, when the parts in the system function as described above. In this manner a 10 difference is maintained between the inside and outside temperatures, and it will now be seen that, by adjusting the various parts, any cycle stops and expansion coil 36 does not abpractical temperature difference may be' eill-. ciently and dependably maintained.

'Let it now be assunfed that the outside tem perature falls below 68 F. Thusi-t becomes necessary to heat space 10 in order to maintain a comfortable temperature instead of refrigerating the air passing therethrough. When the temperature outside-spacelo is 68 or below, thermostatic bellows 148 is actuated to move contact member 141 intoengagement with stops 142 and 143. As member 141 assumes this position, arm 134, and consequently contact 136, may move in a counterclockwise direction without the possibility of contact -138 following this movement.

If the temperature inside space 10 falls below 4 68 F., the inside thermostatic bellows 131 exerts a tension on arm 134 to swing this arm. in a counterclockwise direction and bring contact 137 into engagement with contact 139. A circuit is now established between battery 162 and valve 127, and, as described above, this valve opens. The opening of valve 127 allows air under pressure to pass from 'pipes 97 and 126 through the valve and into pipe 128 to the actuating parts of valve 61. Thus valve 61 is opened and steampasses from pipes S and 59 through valve 61 and thence into steam coil 58 (Figure 2)- through pipe 62. Coil 58. is heated and the air being forced past it by fan 15 is heated and the air thus heated passes through conduit 11 and outmoves'contact 137 out of engagement with con-.

tact 139, thus breaking the circuit between valve 127 and battery 162. Valve 127'closes as does valve -61, stopping the circulation of steam through coil 58 and the heating of the incoming air ceases.

A subsequent decrease in temperature inside of space lO effects a movement of arm 134 and contact 137 toward the left or in a counterclockwise direction to reestablish the circuitto the 'electro-magne'tic means operating valve 127; in

this manner the heating operation continues until the desired inside temperature is reestablished. These cycles of heating operations are continuously repeated under the==control of inside thermostatic bulb 129 asneeded to keep the temperature inside space 10 at 68 F. as long as the temperature outside of space 10 is at or below 68 F., for under the latter conditions, .arm 149 is held so that contact 152 is in continuous engagement with contact 153 through the action of thermostatic bellows 148.

Should it be desirable to prevent the lowering of the inside temperature below a temperature other than the above assumed 68. F., adjustable contacts 139 and 153 are correspondingly resetin accordance with the values as indicated on the temperature scales 140 and 155, respectively. Also it may be desired to prevent the heating action inside space '10 as long as the temperature outside space 10 is at or above a temperature other than the above assumed 68 F'., and in this case contact .153 is correspondingly reset.

It will thus be seen that there has been providedin this invention a system and apparatus in which the various objects hereinabove noted together with many thoroughly practical advantages are successfully achieved. Further, itv

will be seen that the apparatus in our system is of thoroughly dependable action and is well adapted to meet a great variety of possible practical conditions met with in practice of which the purely illustrative examples above described in detail are but a few.

As many possible embodiments may be made in this invention, and as many steps may be made in the embodiments above set forth or in the steps hereinbefore set forth, it is to be understood that all matter hereinabove described or set forth in the accompanying drawings is to be interpreted as illustrative and not in a limiting 861186.

said space as the outside temperature varies;

. and means for rendering said adsorbing means inoperative, thereby to prevent refrigeration, when the outside temperature reaches a certain minimum value.

2. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, means in said refrigeration unit adapted to rendersaid refrigeration unit effective when heated and adapted to render said refrigeration unit ineffective when cooled, and means responsive to a function of the temperature outside said space and of the temperature inside said space for controlling the cooling and heating of said last-mentioned meansto cause said refrigeration unit to maintain apredetermined difference between the outside and inside temperatures.

3. In apparatus of the character described, in combination, means forming a space whose temperature is tobe regulated, a refrigeration unit for said space including means dependent for. operationupon the application of heat, temperature responsive means inside said space and outside said space coacting with each other to controlthe heating of said last-mentioned means, and means for fixing the range of coaction of said temperature-responsive means to maintain a predetermined difference between the temperatures within said space and outside said space irrespective of outside temperature variation.

4. In apparatus of the character described, in combination, means forming a space whose atmosphere is to be conditioned, refrigeration means for said space including means dependent for operation upon the application of heat thereto, heating means for said space, means responsive to the temperatures outside said space and inside said space coacting to control the heating of said heat-responsive means by said heating means, and means causing a certain predetermined difference between the temperatures inside said space and outside said space to be maintained when one of said temperatures is above a certain limit irrespective of temperaturevariations above said limit.

5. In apparatus of the character described, in

last-mentionedmeans to cause a certain prede- 'termined difference between the temperatures inside said space and outside said space to be maintained when one of said temperatures is above'a certain limit, and means for preventing the heating of said heat-responsive means and for causing the action of said heating means when said last-mentioned temperature is below said limit:

6; In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, refrigeration means for said space including adsorbing means adapted to render said refrigeration means effective upon the application of heat thereto, heating means for said space, circuits controlling the heating of said adsorbing means and the action of said space-heating means, and temperature responsive means outside. said space and inside said space electrically interlocked with said circuits for controlling the heating of said adsorbing means and the action of said space-heating means to maintain a certain predetermined difference between the inside and outside temperatures when said outside temperature reaches or exceeds a certain predetermined limit and for maintaining a substantially constant temperature in said space when said outside temperature falls below said limit.

7. In apparatus of the character described, in

combination, means for passing a medium into thermal relation to a space whosetemperature is to be regulated, refrigeration means for cooling said medium, heat-responsive means in said refrigeration means dependent for operation upon the application of heat thereto, heating means for heating said medium, temperature responsive means for selectively controlling the application of 'heat to said heat-responsive means and the action of said heating means, and means coacting with said last-mentioned means for maintaining a certain predetermined difference between the temperatures outside said space and inside said: spacewhen said outchanges.

side temperature attains any point above a predetermined limit.

8. In apparatus of the character described, in combination, means for passing a medium into thermal relation to a space whose temperature is to be regulated, refrigeration means for cooling said medium including a device operatively responsive to the application of heatthereto, heating means for heating said medium, temperature responsive means outside said space for selectively controlling the action of said heating means and the application of heat to said heat responsive means, and temperature responsive means inside said space coacting with said last-mentioned temperature responsive means to maintain a fixed difference between the temperatures outside said space and inside said space when one of said temperatures is above a certain limit and for causing the action of said heating means when the temperature of said space falls below a certain limit.

9. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, refrigeration means for said space, means included in said refrigeration means operatively responsive to the application of heat, means for heating said lastmentioned means to render said refrigeration means effective to maintain a predetermined difference in temperature between the outside and inside of said space as the outside temperature varies, means preventing said last-mentioned action when the outside temperature reaches a certain minimum value, and means causing the heating of said space when the outside temperature recedes below said minimum value.

10. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, means including heat-responsive means for cooling said space, means responsive to the temperature inside of said space, means responsive to the temperature outside of' said space, and means causing the heating of said heat-responsive means to render said second mentioned means effective when said two temperature responsive means respond to temperatures whose difference is equal to or greater than a certain value.

11. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space and including means for adsorbing a gaseous refrigerant released therefrom upon said adsorbing means being heated, means for heating said adsorbing means, means .for cooling said adsorbing means, means for con-' trolling the action ofsaid two last mentioned means, and temperature responsive means in said space and outside said space for controlling the action of said controlling means to maintain a certain fixed difference between the temperatures outside of said space and inside of said space irrespective of outside temperature 12. In apparatus-of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, adsorbing means in said refrigeration unit operatively responsive to temperature changes, means for heating said adsorbing means, means for cooling said adsorbing means, means forcontrolling the action of said two last mentioned means, heating means for said space, and temperature responsive means in said space and outside said space for controlling the action of said controlling means and said heating means to maintain a certain predetermined difference between the temperatures outside of said space and inside of said space irrespective of outside temperature variation.

13. In apparatus of the character described, in combination, means forming aspace whose temperature .is to be regulated, a refrigeration unit including alternately acting adsorbers, means for cooling said adsorbers, means for heating said adsorbers, means for controlling the action of said last two mentioned means, means responsive to the temperature within said space, and means responsive to the temperature outside said space, said temperature responsive means coacting to control said controlling means to maintain a certain predetermined difference between the temperature within said space and outside said space irrespective of outside temperature changes.

14. In apparatus of the character described,

in combination, means forming a' space whose I temperature is to be regulated, a refrigeration unit. utilizing a gaseous refrigerant, means adapted upon being heated to release said re-,

frigerant and upon being cooled'to take up said refrigerant, pressure-responsive means for heating said second mentioned means, pressure-responsive means for cooling said second mentioned means, pressure-applying means for controlling the action of said last two mentioned means, and temperature responsive means for controlling the action of said pressure-applying means to maintain a predetermined difference between the temperature outside said space and inside said space, when the outside temperature.

is above a certain predetermined limit.

16. In apparatus of the character described, in combination, meansforming a space whose temperature is tobe regulated, a refrigeration unit utilizing a gaseous refrigerant, means adapted upon being heated to release said refrig erant and upon being cooled to take up said'refrigerant, pressure-responsive means for heating said second mentioned means, pressure-responsive means for cooling said second mentioned.

means, heating means for said-space, pressureapplying means for controlling the action of said last two mentioned means, and temperatu're' responsive means for controlling the action'of said pressure-applying means and said heating means. 17. In apparatus of the character described,

vin combination, means forming a space whose temperature is to be regulated, a refrigeration -unit utilizing a gaseous refrigerant, means adapted upon being heated to release said refrigerant and upon being cooled to take up said refrigerant, means for heating said second mentioned' means, means for cooling. said second mentioned means, said last two mentioned means operatively responsive to the application of pressure, pressure-applying means for controlling the action' of said last two mentioned means, a switch-responsive to temperature changes, and electrical control means controlled by said switch for controlling said pressure-applying means.

18. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit utilizing a gaseous refrigerant, means adapted upon being heated to release said refrigerant and upon being cooled to take up said refrigerant, means for heating said second mentioned means, fluid-controlled means for controlling said heat,- ing means, means for cooling said second mentioned means, fluid-controlled means for controlling .said cooling means, and temperature responsive means for controlling the application of fluid to said two fluid-controlled means.

19. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit utilizing a gaseous refrigerant, means adapted upon being heated to release said refrigerant and upon being cooled to take up said refrigerant, means for passing aheated fluid into thermal relation to said second mentioned means and adapted to be actuated upon the application of fluid under pressure thereto, means for passing a cooling fluid into thermal relation to said second mentioned means and adapted to be actuated upon the application of fluid under pressure thereto, and temperature responsive means for controlling-the application of'fluid to said two last-mentioned means.

'20. In apparatus of the character described,'

in combination, means forming a space whose unit utilizing a gaseous refrigerant, means adapted upon being heated to release said re-' frigerant and upon being cooled to take up said refrigerant, means for passing a heated fluid into thermal relation to said second-mentioned means and adapted to be actuated upon the application of fluid under pressure thereto, means for passing a cooling fluid into thermal relation to said second-mentioned means and adapted to be actuated upon the application of fluid under pressure thereto, heating means for said space, and temperature responsive means for controlling the action of said heating means and the action of said two fluid-actuated means.

21. In. apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit utilizing a gaseous refrigerant, a member adapted to take up gaseous refrigerant when cooled and to release refrigerant when heated, a second member adapted to takeup gaseous refrigerant when cooled and to release said refrigerant when heated, means for alternately heating said two members, means for alternately cooling said two members, and temperature responsive means including fluid-operated means for controlling the action of said last two mentioned means.

' 22. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit utilizing a gaseous refrigerant, a member adapted to take up gaseous refrigerant when cooled and to release refrigerant when heated, a second member adapted to take up gaseous refrigerant when cooled and to release said refrigin combination, means forming a space whose temperature is to be regulated; a refrigeration unit for cooling said space and utilizing a gaseous refrigerant and including a member adapted to take up gaseous refrigerant when cooled and to release said refrigerant when heated, a second member adapted to take up gaseous refrigerant when cooled and to release said refrigerant when heated, means for alternately heating said two members, means for alternately cooling said two members; heating means for said space; pressureresponsive means for controlling the said refrigeration unit; and temperature responsive means for controlling the action of said pressure-responsive means and said last-mentioned heating means.

24. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit utilizing a gaseous refrigerant, a member adapted to take up gaseous refrigerant when cooled and to release said refrigerant when heated, a second member adapted to take up gaseous refrigerant when cooled and to release said refrigerant when when heated, means for alternately passing a heated fluid into thermal contact with said two members, means for alternately passing a heatabstracting fluid into thermal contact with said two members, controlling means for said two last mentioned means responsive to the application of pressure, means for applying pressure to said controlling means, and temperature responsive means for controllingsaid last-mentioned means. 25. In apparatus of .the character described, in combination, a medium whose temperature is to be regulated, a refrigeration unit utilizing a gaseous refrigerant for cooling said medium and including means adapted upon being heated to release said gaseous refrigerant and upon 'being cooled to take up said gaseous refrigerant, means for heating said first mentioned means operatively responsive to the application of pressure,

means for cooling said first mentioned means of pressure, means for cooling said first men-' tioned means operatively responsive to the ap-.

plication of pressure, heating means for said medium, and temperature responsive means for controlling the application of pressure to said two last-mentioned means and for controlling the operationof said heating means.

27. In apparatus of the characterdescribed, in combination, means forming a space whose temperature is to be regulated,- a refrigeration unit for said space, alternately actuated adsorbing members in said refrigeration unit, and temperature responsive means for controlling the action of said adsorbing members to maintain a predetermined difference between the temperature within said space and the temperature outside of said space when said outside temperature is at any point above a certain predetermined limit.

28.- In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, alternately actuated adsorbing means in said refrigeration unit, heating means for said space, temperature responsive means for controlling the action of said heating means and said adsorbing members to maintain a pre-' determined difference between the temperature within the space and the temperature outside of the space when the temperature outside said space is above a certain limit.

29. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, adsorbing members in said refrigeration unit, means for alternately heating and cooling said adsorbing members, and temperature responsive means for controlling the action of said last-mentioned means to maintain a predetermined difference between the temperature within said space and the temperature outside of said space irrespective of temperature changes above a certain limit.

30. In apparatus of the character described,

in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, adsorbing members in said refrigeration unit, means for alternately heating and cooling said adsorbing members, a heating device for said space, and temperature responsive means for controlling the action of said secondmentioned means to maintain a predetermined difference between the temperature within said space and outside of said space when the temperature outside said space is above a certain value and for affecting said heating device when the temperatures within and outside said space are below certain values.

31. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, adsorbing members in said refrigeration unit, means for alternately heating said adsorbing members, means. for alternately cooling said adsorbing members, fluid-actuated means for controlling said last two mentioned means, and means controlling the supply of fluid to said fluid-actuated means in accordance with temperature changes within said space.

32. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit for said space, adsorbing members in said refrigeration unit, means for alternately passing a heating fluid into thermal contact with said adsorbers, means for alternately passing a cooling fluid into thermal contact with said adsorbers, fluid-operated means forcontrolling the action of said last two mentioned means, and temperature responsive means for controlling said fluid-operated means in accordance with temperature changes within said space.-

33. A railroad car having a steam'line and whose interior temperature is to be regulated, a refrigeration unit openatively related to said interior, adsorbing means in said refrigeration unit, means for cooling said adsorbing means, means for passing steam from said steam line into thermal contact with said adsorbing means, and means responsive to temperature for controlling the action of said last two mentioned means.

34. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit utilizing a gaseous refrigerant, means adapted upon being heated to release said refrigerant and upon being cooled to take up said refrigerant, means forv heating said second-mentioned means, fluid-controlled means for controlling said heating means, means for cooling said second-mentioned means, fluid-controlled means for controlling said cooling means, and temperature responsive means for controlling the application of fluid to said two fluid-controlled means to maintain a predetermined difference between the temperature of said space and the temperature outside of said space irrespective of temperature changes outside said space.

-35. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit utilizing a gaseous refrigerant, means adapted upon being heated to release said refrigerant and upon being cooled to take up said refrigerant, means for passing a heated fluid into thermal relation to said second-mentioned means and adapted to be actuated upon the application of fluid under pressure thereto, means for passing a cooling fluid into thermal relation to said stant predetermined temperature within said space when said outside temperature is below a certain limit.

36. In apparatus of the character described, in combination, means forming a space whose temperature is to be regulated, a refrigeration unit utilizing a gaseous refrigerant, a member adapted to take up gaseous refrigerant when cooled and to release refrigerant when heated, a second member adapted to take up gaseous refrigerant when cooled and to release said refrigerant when heated, means for alternately heating said two members, means for alternately cooling said two members, pressure responsive means for controlling the action of said last two mentioned means, and temperature responsive means for controlling the action of said "pressure responsive means to maintain a predetermined difference between the temperature of' GEORGE E. HULSE. JOHN D. STROBEIL. 

